Three-dimensional (3D) printing, or additive manufacturing, may be used to make 3D objects. In particular, metallic 3D printing can be used to make 3D metal objects. The objects can be of any shape or geometry, and may be based off of a 3D model or other electronic data source. In so doing, metallic 3D printing may eliminate shape restrictions, time and cost expenses of typical casting techniques used to produce the same objects.
To produce an object, a 3D printer deposits successive layers of a metallic material in powder form on top of a metal build plate, or substrate, under computer control. The 3D printer may employ techniques, such as, selective laser sintering, in order to bind the metallic material together to create a solid structure on the build plate. More specifically, a computer-controlled laser beam may sinter the metallic material on the build plate in a vertically additive, layer-by-layer fashion.
For the metallic material to weld or bond to the build plate during processing, typically a build plate material is of a similar or same material as the metallic material of the object to be produced. After the object is completely formed on the build plate, the object is removed from the build plate via a cutting operation, such as, saw cutting, electric discharge machining, milling, and the like. However, such removal processes may be time-consuming, expensive, and may damage the object. In addition, if the build plate is to be used again for another build, it must be refurbished. Furthermore, when the build plate is made of the same material as the object, such as titanium, the cost of the build plate can be particularly expensive for a piece that will eventually be discarded.
A selective laser melting process is disclosed in U.S. Pat. No. 8,610,027, entitled, “Process for Producing a 3-Dimensional Component by Selective Laser Melting (SLM).” The '027 patent describes initially applying a separating layer to the surface of the platform before applying powdered layers of material for the component. The separating layer is produced from a different material as a material of the component. In the '027 patent, the separating layer can be produced by applying one or more layers of a metal foil or metal powder, the melting point of which is lower than the melting point of the component to be produced. While effective, improvements are still desired to provide a more efficient and cost-effective detachment technique for objects made from metallic 3D printing.